Aftersales is shocking...

I make my own clothes and Dec 2017 I got an empisal over locker to upgrade the one I currently had. This new one was keeps on falling apart after little use. I took it in, got repaired. a few weeks later, same issues again. Machine falls apart. Took it in , got voucher, thinking I will get another one, as maybe that one is just a dud.... after a few uses, same problem, machine falls apart. Took it back to game today 14 Dec 2017, told them this is not a good machine, I'm not happy with it, it keeps on breaking falling apart ect… So I told game, I want my money back, as you don't sell any other over lockers. They are now sending it back again to get fixed. How many times must this happen before I get my money back. This is clearly a faulty design. I went on some groups on Facebook and they are complaining about the same thing, where you have put stoppers on the edges to keep it together while sewing. I'm sorry , but that is not acceptable for me. A serger should work fine with me having to tape and push stoppers in it to keep it from falling apart.